Measuring & Documenting disparities in Periodontal Disease

Objectives: Although periodontal health disparities have been documented over the years and some studies have attempted to examine trends over time, it has been challenging to estimate the magnitude and direction of these disparities across groups due to the lack of a uniform or standard methodology to measure this disparity and its trend over time. Methods: This study uses data from NHANES III to develop methods to measure and document disparities in periodontal disease (PDs) accounting for the reference group (RG) used and the type of measure, absolute (AM) or relative (RM). Analysis was limited to non-Hispanic black (NHB), non-Hispanic white (NHW) and Mexican American (MA) adults 18 years and older. PDs was defined as a combination of at least three sites with CAL > 4mm and at least two sites with PD > 3mm. All analyses were performed in SUDAAN to account for the complex sampling design. Results: The overall prevalence of PDs was 7.3% with NHB exhibiting the highest (11.2%). There was no difference in prevalence between MA (6.9%) and NHW (6.5%). Using the overall population as RG, NHB were 1.6 times more likely to have PDs; while using NHW as RG, increases the estimates to 1.8. Using an AM instead of a RM for comparisons, the use of overall population as RG for NHB yielded a difference of 3.9%; while NHW as RG, the estimate for NHB increases to 4.7%. Conclusions: The use of the overall population as the RG decreases the magnitude of the burden of PDs experienced by NHB. With regard to the type of measure used, clearly the use of the overall population as the RG affects the magnitude of the problem in NHB. Thus, the choice of RG and type of measure may affect the documentation of disparities. Supported by NIDCR and RWJ.